Crabs are commercially harvested by placing crab pots in areas where crabs are present. Bait that is attractive to crabs is placed in these crab pots and crabs enter the pots in search of the bait. The crab pots are enclosure-type trapping devices that crabs may enter but, in theory, cannot leave.
During use, the pots are tied to a buoy using a line. The buoy floats above the pot to mark the location of the pot. After a suitable period of time has passed, the crabber locates the pot using the buoy and lifts the pot using the line.
As crab pots are immersed in salt water and submitted to fairly extreme conditions during use, their design has been kept fairly simple and rugged. The basic design of a crab pot has remained unchanged for many decades.